Incidence of periodontal disease(s) is age-dependent and may reflect a declining host resistance to various oral environmental insults. Information indicates that dermal specificity regulates the acquisition and maintenance of epithelial phenotypes during development, maturation and senescence. Properties intrinsic to dermal stroma regulate properties within the gingival crevicular epithelia in Man. Recent information clearly indicates that dermal-epidermal diffusion of specific essential amino acids and other nutrients demonstrate age- dependent diffusion patterns in "clinically normal" human gingival biopsies. Age-dependent ultrastructural alterations have also been observed in keratinized and non-keratinized gingival tissues. Studies are proposed to extend these diffusion and morphological observations and to compare these findings with alterations in various stages of periodontal disease(s). Therefore, ultrastructural, autoradiographic, biochemical and immunological studies will extend age-dependent observations on clinically normal human gingival biopsies in vitro to include specimens obtained from diseased biopsy materials. An additional aspect will be to evaluate pre- and post-treatment responses in periodontally-treated patients using ultrastructural and autoradiographic criteria. Studies are designed to isolate and make antibodies to keratohyalin granules and several other key constituents of the keratinization process. Studies are also designed to study cementogenesis in animal and human specimens; to isolate and produce antibodies to enamel-like proteins and to study alterations in this material associated with the disease process. These studies will provide diagnostic criteria with which to evaluate several of the significant components associated with periodontal disease(s).